Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F10/00—Thin magnetic films, e.g. of one-domain structure
  • H01F10/08—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers
  • H01F10/10—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition
  • H01F10/18—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition being compounds
  • H01F10/193—Magnetic semiconductor compounds
  • H01F10/1936—Half-metallic, e.g. epitaxial CrO2 or NiMnSb films
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  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
  • H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
  • H01L29/82—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by variation of the magnetic field applied to the device
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
  • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
  • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
• • G—PHYSICS
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  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
  • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
  • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
  • G11B5/3906—Details related to the use of magnetic thin film layers or to their effects
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
  • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
  • G11B5/3903—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
  • G11B5/3906—Details related to the use of magnetic thin film layers or to their effects
  • G11B5/3909—Arrangements using a magnetic tunnel junction
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/7368—Non-polymeric layer under the lowermost magnetic recording layer
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/7368—Non-polymeric layer under the lowermost magnetic recording layer
  • G11B5/7371—Non-magnetic single underlayer comprising nickel
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/7368—Non-polymeric layer under the lowermost magnetic recording layer
  • G11B5/7373—Non-magnetic single underlayer comprising chromium
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/739—Magnetic recording media substrates
  • G11B5/73911—Inorganic substrates
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/739—Magnetic recording media substrates
  • G11B5/73911—Inorganic substrates
  • G11B5/73917—Metallic substrates, i.e. elemental metal or metal alloy substrates
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/739—Magnetic recording media substrates
  • G11B5/73911—Inorganic substrates
  • G11B5/73917—Metallic substrates, i.e. elemental metal or metal alloy substrates
  • G11B5/73919—Aluminium or titanium elemental or alloy substrates
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/62—Record carriers characterised by the selection of the material
  • G11B5/73—Base layers, i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
  • G11B5/739—Magnetic recording media substrates
  • G11B5/73911—Inorganic substrates
  • G11B5/73921—Glass or ceramic substrates
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11C—STATIC STORES
  • G11C11/00—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor
  • G11C11/02—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements
  • G11C11/16—Digital stores characterised by the use of particular electric or magnetic storage elements; Storage elements therefor using magnetic elements using elements in which the storage effect is based on magnetic spin effect
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
  • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
  • H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers
  • H01L27/04—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being a semiconductor body
  • H01L27/10—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having potential barriers; including integrated passive circuit elements having potential barriers the substrate being a semiconductor body including a plurality of individual components in a repetitive configuration
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N50/00—Galvanomagnetic devices
  • H10N50/10—Magnetoresistive devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B82—NANOTECHNOLOGY
  • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
  • B82Y25/00—Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• • G—PHYSICS
  • G11—INFORMATION STORAGE
  • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
  • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
  • G11B5/127—Structure or manufacture of heads, e.g. inductive
  • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
  • G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
  • G11B2005/3996—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F10/00—Thin magnetic films, e.g. of one-domain structure
  • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
  • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
  • H01F10/3254—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F10/00—Thin magnetic films, e.g. of one-domain structure
  • H01F10/32—Spin-exchange-coupled multilayers, e.g. nanostructured superlattices
  • H01F10/324—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer
  • H01F10/3268—Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer the exchange coupling being asymmetric, e.g. by use of additional pinning, by using antiferromagnetic or ferromagnetic coupling interface, i.e. so-called spin-valve [SV] structure, e.g. NiFe/Cu/NiFe/FeMn

Definitions

• the present invention is applied to a functional device that controls electron spin, particularly a super-gigabit large-capacity, high-speed, nonvolatile magnetic memory, and a spin-injection device for enabling spin-injection magnetization reversal with a smaller current density.
• the present invention relates to a spin injection magnetic memory device used and a spin injection magnetic memory device.
• the present invention also relates to a magnetic thin film having a large spin polarizability, a magnetoresistive element using the same, and a magnetic device. Tall.
• GMR giant magnetoresistance
• MT J magnetic field sensors and magnetic memories
• the GMR controls the magnetization of the two ferromagnetic layers in parallel or antiparallel to each other with an external magnetic field, so that the giant magnetoresistance effect is obtained due to the fact that the resistance differs from each other due to spin-dependent scattering at the interface. ing.
• the MTJ controls the magnetization of the two ferromagnetic layers in parallel or anti-parallel with an external magnetic field, so that the tunnel currents in the direction perpendicular to the film surface are different from each other.
• TMR TMR
• Tunnel magnetoresistance TMR depends on the spin polarizability P at the interface between the ferromagnetic material and the insulator used, and if the spin polarizabilities of the two ferromagnetic materials are P 1 and P 2 respectively, then It is known that this is given by equation (1).
• TMR 2P, P 2 / ( 1 -P, P 2) (1)
• the spin polarization P of the ferromagnetic has a value of 0 ⁇ P ⁇ 1.
• the maximum tunneling magnetoresistance TMR at room temperature obtained is about 50% when a C0Fe alloy with a P of 0.5 is used.
• MRAM nonvolatile magnetic memories
• the MTJ elements are arranged in a matrix, and a current is applied to a separately provided wiring to apply a magnetic field, thereby controlling the two magnetic layers constituting each MTJ element to be parallel and antiparallel to each other. Record “1” and "0". Reading is performed using the TMR effect.
• MRAM nonvolatile magnetic memories
• a three-layer structure in which two magnetic layers are coupled to each other in an anti-parallel manner via a non-magnetic metal layer (artificial antiferromagnetic film, Synthetic Ant if error magnet; (See, for example, Japanese Patent Application Laid-Open No. 9-251621).
• a non-magnetic metal layer artificial antiferromagnetic film, Synthetic Ant if error magnet;
• the use of such a SyAF structure reduces the demagnetizing field, so the magnetic field required for magnetization reversal is reduced even if the element size is reduced.
• JC Slonczewski "Urrent-driven exit aTion of magnetic multilayers", (1996), J. Magn. Magn. Mater.
• the spin inversion method has been theoretically proposed and realized experimentally (for example, JA Katine, FJ Albert, RA Ruhman, EB
• the spin inversion method has a three-layer structure including a first ferromagnetic layer 101 / nonmagnetic metal layer 103 / second ferromagnetic layer 105, as shown in FIG.
• a current is applied to the second ferromagnetic layer 103 and the first ferromagnetic layer 101, the second ferromagnetic layer 101 spin-polarized electrons are injected into the magnetic layer 1 0 5, are those that the spin of the second bow firefly magnetic '! 1 Namaso 1 05 is inverted, spin This is called magnetization reversal by injection.
• the spins of the first ferromagnetic layer 101 and the second ferromagnetic layer 105 become antiparallel. Therefore, in the spin-transfer magnetization reversal of the two-layer structure, the spins of the first and second ferromagnetic layers can be made parallel or antiparallel by changing the direction of the current.
• GMR giant magnetoresistive
• MRAM magnetic random access magnetic memory
• the giant magnetoresistive element has a giant magnetoresistive element with a current-in-plane (CIP) structure that allows current to flow in the film plane, and a current-perpendicular to the plane (CPP) that has a current flowing in the direction perpendicular to the film plane.
• CIP current-in-plane
• CPP current-perpendicular to the plane
• a giant magnetoresistive element having a structure is known.
• the principle of a giant magnetoresistive element is spin-dependent scattering at the interface between a magnetic layer and a nonmagnetic layer.
• a giant magnetoresistive element having a CPP structure has a larger GMR than a giant magnetoresistive element having a CIP structure. .
• a spin-valve type in which an antiferromagnetic layer is brought close to one of the ferromagnetic layers and the spin of the ferromagnetic layer is fixed is used.
• the electric resistivity of the antiferromagnetic layer is about 200 ⁇ cm, which is about two orders of magnitude larger than that of the GMR film, so that the GMR effect is weakened.
• the value of the magnetoresistance of a giant magnetoresistance effect element with a spin-valve CPP structure is 1% Less than the following. For this reason, giant magnetoresistive elements with a CIP structure have already been put to practical use in hard disk playback heads, but giant magnetoresistive elements with a CPP structure have not yet come into practical use.
• tunnel magnetoresistive element by controlling the magnetization of the two ferromagnetic layers to be parallel or antiparallel to each other by an external magnetic field, the magnitude of the tunnel current in the direction perpendicular to the film surface is different.
• Tunnel magnetoresistance (TMR) effect is obtained at room temperature (T. Miyazaki and N. Tezuka, "Spin polarized tunneling in fer romagne t / insu 1 ator / fer romagne t junctions", (1995), J. Magn. Magn. Mater, L39, p.1231).
• TMR elements are expected to be applied to magnetic heads for hard disks and non-volatile random access magnetic memories (MRAM).
• MRAM non-volatile random access magnetic memories
• the MTJ elements are arranged in a matrix, and a current is applied to a separately provided wiring to apply a magnetic field, so that the two magnetic layers constituting each MTJ element are parallel and antiparallel to each other. By controlling, "1" and "0" are recorded. Reading is performed using the TMR effect.
• MRAM if the element size is reduced for higher density, there is a problem that the noise due to the variation of the element increases and the TMR value is insufficient at present. Therefore, it is necessary to develop devices that exhibit larger TMR.
• the spin injection method is promising as a spin inversion method for future nanostructure magnetic
• current density required for magnetization reversal by spin injection is very large and I 0 7 A / cm 2 or more, which is This was a practical problem to be solved.
• the present inventors have developed a three-layer structure in which the two ferromagnetic layers are coupled to each other in an anti-parallel manner via a non-magnetic metal layer. It has been found that when current flows from the layer, magnetization reversal by spin injection can occur at a lower current density.
• the miniaturization of the giant magnetoresistive effect element having the CIP structure which has been put to practical use in the conventional reproducing head of a hard disk, has been promoted to achieve a high recording density, the signal voltage has been increased due to the miniaturization of the element. Is expected, and a high-performance CPP structure giant magnetoresistive element is required instead of the CIP structure giant magnetoresistive element, but this has not been realized yet.
• the conventional half-metal thin film requires substrate heating and heat treatment to obtain its structure, which increases the surface roughness or oxidizes, which is one of the reasons that a large TMR cannot be obtained. Is considered one.
• a thin film may not exhibit half-metal characteristics on the surface, and the half-metal characteristics are sensitive to the composition and the order of the atomic arrangement. The difficulty in obtaining the electronic state of the half-metal at this time is also presumed to be the reason that a large TMR cannot be obtained. From the above, there is a problem that fabrication of a half metal thin film is actually very difficult, and a favorable half metal thin film that can be used for various magnetoresistive elements has not been obtained.
• L 2 is a conventional full-Heusler alloy, similarly to the mold compound, or shows a Co 2 CrAl and Co 2 F e 0 .4 Cr 0 .6
• a 1 thin film is experimentally half metal characteristics and large TMR characteristics I don't know at all.
• the present invention provides a spin injection device capable of performing spin injection magnetization reversal with a smaller current density, a magnetic device using the spin injection device, and a magnetic device. It is an object of the present invention to provide a memory device.
• an object of the present invention is to provide a magnetic thin film having a large spin polarizability, a magnetoresistive element using the same, and a magnetic denos.
• a spin injection device includes a spin injection portion having a spin polarization portion and an injection junction, and a spin injection portion having a magnetization antiparallel magnetically coupled through a nonmagnetic layer.
• a Sy AF having a first magnetic layer and a second magnetic layer having different sizes, wherein the Sy AF and the injection junction are joined, and a spin-polarized electron is injected from the spin injection part and the second injection is performed.
• the configuration is such that the magnetizations of the first magnetic layer and the second magnetic layer are reversed while maintaining the antiparallel state.
• the injection junction of the spin injection part can be any one of a nonmagnetic conductive layer and a nonmagnetic insulating layer.
• Spin-polarized electrons can be made spin-conducting conductive or tunnel-joinable at the injection junction of the spin-injection.
• the spin polarization part of the spin injection part may be a ferromagnetic layer.
• the spin polarization section of the spin injection section may be provided in contact with the antiferromagnetic layer for fixing the spin of the ferromagnetic layer.
• the aspect ratio of the first magnetic layer and the second magnetic layer of SyAF joined to the injection junction of the spin injection part is 2 or less.
• the spin injection device of the present invention can cause the magnetization reversal with a smaller current density.
• the spin injection magnetic device further comprising a first magnetic layer and a first magnetic layer having different magnetization magnitudes magnetically coupled in antiparallel via a nonmagnetic layer, and A free layer capable of reversing the magnetization while maintaining the antiparallel state of the magnetization of the layer and the second magnetic layer, and a ferromagnetic fixed layer tunnel-joined via a free layer and an insulating layer.
• the structure is such that the layers are ferromagnetic spin tunnel junctions.
• a spin injection unit having an injection junction and a spin polarization unit for bonding to the free layer may be provided.
• the injection junction of the spin injection part can be any one of a non-magnetic conductive layer and a non-magnetic insulating layer.
• Spin-polarized electrons may be made spin-conducting conductive or tunnel-junctionable at the injection junction of the spin injection.
• the spin polarization part of the spin injection part can be a ferromagnetic layer.
• S The spin polarization section of the pin injection section may be provided in contact with the antiferromagnetic layer for fixing the spin of the ferromagnetic layer.
• the aspect ratio of the first magnetic layer and the second magnetic layer of the free layer joined to the injection junction of the spin injection part can be set to 2 or less.
• the injection junction of the spin injection part may be a word line.
• the spin injection magnetic device of the present invention when spin injection is performed, a single layer of magnetization reversal occurs and becomes parallel or anti-parallel to the magnetization of the fixed layer, so that a tunnel magnetoresistance effect appears. Therefore, the spin injection magnetic device of the present invention can cause the magnetization reversal of the free layer by spin injection at a smaller current density.
• the spin injection unit includes a spin polarization unit including the ferromagnetic fixed layer and an injection junction of the nonmagnetic layer; and a ferromagnetic free layer provided in contact with the spin injection unit.
• the non-magnetic layer is made of an insulator or a conductor, the non-magnetic layer is provided on the surface of the ferromagnetic free layer, and a current flows in the direction perpendicular to the film surface of the spin injection device. It is characterized by reversing the magnetization of the ferromagnetic layer.
• the ferromagnetic free layer is C 0 or a C 0 alloy
• the nonmagnetic layer provided on the surface of the ferromagnetic free layer is a Ru layer
• the film thickness is 0.1 to 20 nm. Is preferred.
• the spin injection device is a spin injection unit including a spin polarization unit including a ferromagnetic fixed layer and an injection junction of a nonmagnetic layer, and a ferromagnetic free layer provided in contact with the spin injection unit.
• a non-magnetic layer comprising an insulator or a conductor, a non-magnetic layer and a ferromagnetic layer being provided on a surface of a ferromagnetic free layer, wherein the non-magnetic layer is formed in a direction perpendicular to the film surface of the spin injection device. It is characterized by passing a current and inverting the magnetization of the ferromagnetic free layer.
• the ferromagnetic free layer and the ferromagnetic layer are made of C 0 or C 0 alloy, and the nonmagnetic layer provided on the surface of the ferromagnetic free layer is a Ru layer, and even if the film thickness is 2 to 2 O nm. Good.
• the spin injection device having this configuration when spin injection is performed from the spin polarization portion through the injection junction, the ferromagnetic free layer is reversed in magnetization. Therefore, the spin injection device of the present invention can cause magnetization reversal with a smaller current density.
• a spin injection magnetic device uses the spin injection device according to any one of the fifteenth to eighteenth aspects.
• Spin injection magnetic device of this configuration When the spin injection is performed, the magnetization reversal of the ferromagnetic free layer occurs when the spin is injected, and the magnetization becomes parallel or antiparallel to the magnetization of the ferromagnetic pinned layer. Therefore, the spin injection magnetic device of the present invention can cause the magnetization reversal of the ferromagnetic free layer by spin injection at a smaller current density.
• a spin-injection magnetic memory device uses the spin-injection device according to any one of the fifteenth to eighteenth aspects.
• the spin-injection magnetic memory device can provide a memory device based on magnetization reversal of a ferromagnetic layer by spin injection at a smaller current density.
• the present inventors have produced a Coz F ex Ci — x Al (0 ⁇ x ⁇ 1) thin film, and as a result, this film is ferromagnetic at room temperature, and L 2 is obtained without heating the substrate.
• the inventors have found that any one of the,, B2, and A2 structures can be produced, and have completed the present invention.
• Co 2 F e x Cr formed on the substrate, - x A 1 comprises a thin film, Co 2 F e x C r , - x Al thin film
• Co 2 F e x C r , - x Al thin film This is achieved by having any one of L 2,, B 2, and A 2 structures, and 0 ⁇ x ⁇ 1.
• C o 2 F e x Cr , -x A 1 film may be formed without the child heating the substrate.
• thermal oxidation S i, glass, Mg_ ⁇ single crystal, GaA s single crystal, Al 2 0 3 may be either one of single crystal.
• a buffer layer may be provided between the substrate and the Co 2 F ⁇ CrA1 thin film.
• this buffer layer at least one of Al, Cu, Cr, Fe, Nb, Ni, Ta, and NiFe can be used. According to this configuration, a Co 2 FGxCrA 1 (here, 0 ⁇ x ⁇ 1) magnetic thin film that is bow-fluorescent at room temperature and has a large spin polarizability can be obtained.
• a tunnel magnetoresistive element according to claim 26 has a plurality of ferromagnetic layers on a substrate, and at least one of the ferromagnetic layers has any one of a B2 structure and an A2 structure.
• Co 2 F e x C r Al (where 0 ⁇ x ⁇ 1) It is characterized by that.
• the ferromagnetic layer includes a fixed layer and a free layer, and the free layer
• L 2,, B 2, C o 2 having any one of structures A 2 structure F e x C r -! X A 1 (wherein, 0 ⁇ x ⁇ 1) is preferably made of a magnetic thin film.
• C o 2 F e x C r, _ ⁇ A 1 thin film can be formed regardless to Caro heat the substrate.
• the substrate is thermally oxidized S i, glass, Mg_ ⁇ single crystal, GaAs single crystal, A l 2 ⁇ 3 may be either one of single crystal.
• the substrate and C o 2 F e x CT - between chi ⁇ Alpha 1 film may buffer one layer is disposed.
• This buffer layer can be composed of at least one of A1, Cu, Cr, Fe, Nb, Ni, Ta, and NiFe. According to the above configuration, a tunneling magneto-resistance effect element having a large TMR can be obtained at room temperature with a low external magnetic field.
• the giant magnetoresistive element according to claim 32 has a plurality of ferromagnetic layers on a substrate, and at least one of the ferromagnetic layers has one of L 2, B 2, and A 2 structures.
• the ferromagnetic layer is composed of a fixed layer and a free layer, and the free layer has any one of L 2, B 2, and A 2 structures C 0 2 FeCr x A 1 (where 0 ⁇ x ⁇ 1) It is preferable that the magnetic thin film is made of a magnetic thin film.
• the Co 2 F x Cri- X A1 thin film can be formed without heating the substrate.
• Between the substrate and the C o 2 F e x C r A 1 film may be arranged buffer one layer.
• the substrate thermal oxidation S i, glass, Mg ⁇ single crystal, GaAs single crystal, and may be either one of A l 2 0 3 single crystal.
• the buffer layer can be composed of at least one of Al, Cu, Cr, Fe, Nb, Ni, Ta, and NiFe. According to the above configuration, a giant magnetoresistance effect element having a large GMR at a low external magnetic field at room temperature can be obtained.
• the magnetic device wherein the C o 2 F e x C r A l (where 0 ⁇ x ⁇ 1) magnetic thin film having any one of B2 and A2 structures is provided on the substrate. It is characterized by being formed on.
• the free layer is the C 0 2 F e x C r , - x A 1 (wherein, 0 ⁇ X ⁇ 1) may be used tunneling magneto-resistance effect element or a giant magneto-resistive element composed of a magnetic thin film .
• the tunnel magnetoresistive element or the giant magnetoresistive element is manufactured without heating the substrate. I have.
• the substrate is thermally oxidized S i, glass, MgO single crystal, it is possible to use a GaAs single crystal, A 1 2 ⁇ 3 tunneling magnetoresistive element was any one of a single crystal or a giant magneto-resistance effect element.
• a tunnel magnetoresistive element or a giant magnetoresistive element using at least one of A1, Cu, Cr, Fe, Nb, Ni, Ta, and NiFe may be used as the buffer layer. According to the above configuration, it is possible to obtain a magnetic device using a magnetoresistive element having a large TMR or GMR at room temperature with a low external magnetic field.
• the magnetic head and the magnetic recording device further include a C 0 2 F x Cr, —A 1 (where 0 0) having any one of L 2,, B 2, and A 2 structures.
• ⁇ x ⁇ 1) It is characterized by being formed on a magnetic thin film plate.
• the free-layer Co 2 F e x C r, -x A 1 (wherein, 0 ⁇ Kai ⁇ 1) using a tunnel magneto-resistance effect element or a giant magnetoresistive effect element is a magnetic thin film You.
• a tunnel magnetoresistive element or a giant magnetoresistive element manufactured without heating the substrate may be used.
• a tunnel magnetoresistance effect element or a giant magnetoresistive effect element buffer layer is disposed between the thin film Is also good.
• the substrate is thermally oxidized S i, glass, MgO single crystal, GaAs single crystal, Al 2 0 3 can be used a tunnel magneto-resistance effect element or a giant magnetoresistive effect element is any one of a single crystal.
• the buffer layer uses a tunnel magnetoresistive element or a giant magnetoresistive element composed of at least one of Al, Cu, Cr, Fe, Nb, Ni, Ta, and NiFe. Good.
• a large-capacity, high-speed magnetic head and a magnetic recording device can be obtained by using a magnetoresistive effect element having a large TMR or GMR at a low external magnetic field at room temperature.
• FIGS. 1A and 1B are conceptual diagrams of a spin injection device according to a first embodiment of the present invention.
• FIG. 1A shows a state in which the spin of SyAF is directed downward
• FIG. FIG. 3 is a conceptual diagram showing a state where
• FIG. 2 is a schematic view of a spin injection device according to the first embodiment in which the injection junction is a nonmagnetic insulating layer.
• FIG. 3 is a schematic view showing a second embodiment of the spin injection device of the present invention.
• FIG. 4 is a schematic view showing a third embodiment of the spin injection device of the present invention.
• FIG. 5 is a schematic diagram illustrating the magnetization reversal of the spin injection device according to the third embodiment. .
• FIG. 6 is a schematic diagram showing a fourth embodiment of the spin injection device of the present invention.
• FIG. 7 is a schematic diagram illustrating the magnetization reversal of the spin injection device according to the fourth embodiment.
• FIG. 8 is a schematic diagram of the spin injection magnetic device of the present invention.
• FIG. 9 is a cross-sectional view of a magnetic thin film that can be used in the present invention.
• FIG. 10 is a cross-sectional view of a modified example of the magnetic thin film that can be used in the present invention.
• Figure 11 shows C o 2 F e x C r!-X A 1 (where 0 ⁇ 1
• FIG. 3 is a diagram schematically illustrating the structure of FIG.
• FIG. 12 is a diagram showing a cross section of a magnetoresistive element using a magnetic thin film according to the second embodiment of the present invention.
• FIG. 13 is a view showing a cross section of a modification of the magnetoresistance effect element using the magnetic thin film according to the second embodiment of the present invention.
• FIG. 14 is a view showing a cross section of a modification of the magnetoresistive element using the magnetic thin film according to the second embodiment of the present invention.
• FIG. 15 is a diagram showing a cross section of a magnetoresistive element using a magnetic thin film according to the third embodiment of the present invention.
• FIG. 16 shows the magnetoresistance effect using the magnetic thin film according to the third embodiment of the present invention. It is a figure showing the section of the modification of an element.
• FIG. 17 is a diagram schematically illustrating resistance when an external magnetic field is applied to a magnetoresistive element using the magnetic thin film of the present invention.
• FIG. 18 is a diagram showing the spin injection magnetization reversal of the spin injection device of Example 1 at room temperature.
• FIG. 19 is a diagram showing the spin injection magnetization reversal of the spin injection device of Example 2 ′ at room temperature.
• FIG. 20 is a diagram showing (a) a magnetoresistance curve and (b) a spin transfer magnetization reversal of the comparative example at room temperature.
• FIG. 3 is a view showing a result of measuring X-ray diffraction of the .5A1 thin film.
• 2 2 is a diagram illustrating a C 0 2 F e 0 .5 C ro.5 A 1 magnetization characteristic at room temperature of the thin film.
• FIG. 23 is a diagram showing the magnetic field dependence of the resistance of the tunnel magnetoresistance effect element shown in FIG.
• FIG. 24 is a diagram showing the magnetic field dependence of the resistance of the tunnel magnetoresistance effect element shown in FIG.
• FIG. 25 is a schematic diagram showing the principle of conventional spin magnetization reversal. BEST MODE FOR CARRYING OUT THE INVENTION
• Fig. 1 is a conceptual diagram of the spin injection device of the present invention, where (a) shows a state in which the spin of SyAF is directed downward, and (b) shows a concept in which the spin of SyAF is directed upward by spin injection.
• FIG. 1 the spin injection device of the present invention 1
• 0 denotes a first magnetic layer 4 and a second magnetic layer 4 via a non-magnetic layer 2 which is a spin injection section 1 having a spin polarization section 9 and an injection junction 7 and an antiferromagnetic yarn ⁇ (,;
• the magnetic layer 6 and the SyAF 3 forming a three-layer structure are provided, and these form a laminated structure.
• the magnetic field Hsw required for the magnetization reversal of a ferromagnetic single-layer film is generally given by the following equation (2) using the uniaxial magnetic anisotropy Ku, the saturation magnetization Ms, the film thickness t, and the width w.
• Hsw 2 Ku / Ms + C (k) t Ms / w (2)
• the first term is a term due to magnetic anisotropy
• the second term is a term due to a demagnetizing field
• the thickness of the two ferromagnetic layers t,, t 2 the saturation magnetization, the magnetization reversal field of SyAF with M 2 is given by the following equation (3).
• the aspect ratio k is t / w. Therefore, in the case of the first magnetic layer 4, it is / w, and in the case of the second magnetic layer 6, it is t 2 / w (see FIG. 1 (a)).
• the SyAF 3 according to the present invention includes a first magnetic layer 4 and a second magnetic layer 6 via a nonmagnetic layer 2. It has a three-layer structure in which the magnetic layers are magnetically coupled antiparallel to each other, and each film thickness is formed in nanometers.
• the non-magnetic layer 2 is a substance that antiferromagnetically couples the magnetization of both magnetic layers via the nonmagnetic layer 2.
• Ruthenium (Ru), iridium (Ir), and rhodium (Rh) can be used as the antiferromagnetic nonmagnetic layer. It is.
• reference numerals 5 and 8 denote terminals through which current flows. Since the ferromagnetic layer and the magnetic layer are conductors, they can also be used as electrodes, but a separate electrode may be provided to allow current to flow.
• the spin of the first magnetic layer 4 and the spin of the second magnetic layer 6 are magnetically coupled while maintaining the antiparallel state. I agree. That is, the magnetization of the first magnetic layer 4 and the magnetization of the second magnetic layer 6 have antiparallel state magnetizations having different magnitudes, that is, antiparallel spins having different magnitudes. Assuming that the thickness of the first magnetic layer 4 is Mi, the magnetization is Mi, the thickness of the second magnetic layer 6 is t 2 , and the magnetization is M 2 , the direction of larger magnetization (t!
• the spin injection part 1 has a structure in which a spin polarization part 9 made of a ferromagnetic layer and an injection junction part 7 made of a nonmagnetic conductive layer are laminated, and the injection junction part 7 of the nonmagnetic conductive layer has a nanometer size. It is.
• the nanometer size means the size of the electron that can conduct while keeping its momentum and spin.
• the injection junction 7 is large enough to allow spin preservation conduction. If the injection junction 7 is a metal, the mean free path of electrons is 1 jLim or less, and this 1; for devices with a size of 1 Lim or less, the injected spins may flow into the other without relaxation. it can.
• the injection junction 7 of the spin injection unit 1 may be a nonmagnetic insulating layer 12 as shown in FIG. This non-magnetic insulating layer 12 has a size of a nanometer that is large enough to allow a tunnel junction through which a tunnel current flows. And a few nm.
• the spin-polarized portion 9 made of a ferromagnetic layer is a ferromagnetic material, but the number of ap spin electrons and down-spin electrons on the Fermi surface that conducts conduction is different.
• the polarized electrons flow into the injection junction 7 of the nonmagnetic metal layer.
• a very small current of 1 milliamperes (mA) or less is passed, and the non-magnetic metal layer ( Alternatively, when spin injection is performed through the injection junction 7 of the nonmagnetic insulating layer 1), the magnetization of the magnetic layer 4 of SyAF 3 and the spin of the magnetic layer 6 are reversed while maintaining the antiparallel state. Therefore, in the spin injection device of the present invention, magnetization reversal by spin injection can be performed at a smaller current density. As a result, spin injection magnetization reversal can be performed only by passing a small current without applying a magnetic field by applying a current, so that a spin injection device having logic, memory, and storage can be realized.
• mA milliamperes
• FIG. 3 is a schematic view showing a second embodiment of the spin injection device of the present invention.
• this embodiment has a structure in which the spin polarization section 9 has an antiferromagnetic layer 21 and a ferromagnetic layer 23, and the ferromagnetic layer 23 has an antiferromagnetic layer 21.
• the spin of the ferromagnetic layer 3 is fixed.
• the injection junction is the nonmagnetic metal layer 25 capable of spin-conserving conduction, an insulating layer capable of tunnel junction may be used instead. In such a configuration, the spin of the spin-polarized portion is fixed and the spin is injected, so that the magnetization reversal of S y A F can be performed.
• FIG. 4 is a schematic diagram showing a spin injection device according to the third embodiment.
• the spin injection device 14 includes a spin polarization section 9 composed of an antiferromagnetic layer 21 and a ferromagnetic pinned layer 26, and an injection junction provided in contact with the ferromagnetic pinned layer. And a two-layer structure including a ferromagnetic free layer 27 and a nonmagnetic layer 28 on the nonmagnetic layer 7.
• the spin injection section 1 is composed of a spin polarization section 9 and an injection junction section 7.
• the spin polarization section 9 the ferromagnetic layer 21 is brought close to the ferromagnetic pinned layer 26 so that the ferromagnetic property is increased.
• the spin of the fixed layer 26 is fixed.
• Injection junction 7 is spin-conserving conductive C
• the nonmagnetic metal layer 25 such as u may be used, but an insulating layer 12 capable of tunnel junction may be used instead.
• the spin injection device 14 of the third embodiment is different from the spin injection device shown in FIG. 3 in that a ferromagnetic free layer 27 and a nonmagnetic layer 28 are provided instead of the Sy AF 3. .
• the nonmagnetic layer 28 is provided at the interface with the ferromagnetic free layer 27 so as to reflect a large number (smallity) spins and transmit a small number (minority) spins. Therefore, the thickness of the nonmagnetic layer 28 may be set to a distance that allows a small number of spins to move while maintaining the spin, that is, the spin diffusion length.
• C 0 or a C 0 alloy can be used as the bow magnetic free layer 27.
• Ru, Ir, and Rh can be used, and it is particularly preferable to use Ru.
• the spin diffusion length of Ru is known to be 14 nm, and the thickness of Ru may be set to 0.1 nm to 20 nm.
• Co or a Co alloy is used for the ferromagnetic free layer 27 and Ru is used for the nonmagnetic layer 28.
• FIG. 5 is a schematic diagram illustrating the magnetization reversal of the spin injection device 14 of the third embodiment.
• FIG. 5 when electrons are injected from the ferromagnetic pinned layer 26 to the ferromagnetic free layer 27, a large number of spin electrons 17 cause the magnetization of the ferromagnetic free layer 27 to change its magnetization. 15 to give a torque of 18.
• the large number of spin electrons 19 reflected at the interface between C 0 or C 0 alloy 27 and Ru 28 shows that the film thickness of C 0 or C 0 alloy 27 indicates that spin conduction is low. If it is thin enough to be preserved, the reflected multiple spin electrons 19 also give the ferromagnetic free layer 27 a similar torque 18. As a result, the torque of the ferromagnetic free layer 27 substantially increases, and becomes the same direction as the magnetization of the ferromagnetic fixed layer 26. On the other hand, when the direction of the current is reversed and electrons are injected from the Ru layer 28 to the C0 or C0 alloy 27 side, a large number of spin electrons are generated by the C0 or C0 alloy 27 and the Ru28.
• the spin injection device 14 of the present invention by inserting the nonmagnetic layer 28, the spin of the spin polarization section 9 is fixed and spin injected, and the magnetization reversal of the ferromagnetic free layer 27 is performed. Can be performed at a lower current density than the conventional spin injection magnetization reversal.
• a spin injection device according to a fourth embodiment will be described with reference to FIG.
• the spin injection device 16 of this embodiment differs from the spin injection device 14 shown in FIG. 4 in that a ferromagnetic fixed layer 29 is further provided on the nonmagnetic layer 28.
• the other configuration is the same as that of the spin injection device 14 shown in FIG.
• the ferromagnetic free layer 27 and the ferromagnetic fixed layer 29 are formed so that their magnetizations are not antiparallel as in Sy AF 3 and that the non-magnetic layer 2 is formed so that spin-conserving conduction occurs.
• the thickness of 8 may be determined.
• the thickness of Ru becomes Sy AF 3
• the thickness may be about 2 to 20 nm so as not to cause the above.
• FIG. 7 is a schematic diagram illustrating the magnetization reversal of the spin injection device 16 of the fourth embodiment. '' When electrons are injected from the ferromagnetic pinned layer 29 to the ferromagnetic free layer 27, many spin electrons 37 are strongly reflected at the interface between the ferromagnetic pinned layer 29 and the Ru layer 28, It does not reach the free layer 27. At this time, if the film thickness of Co or Co alloy 27 is thin enough to maintain spin conduction, few spin electrons 39 are not scattered and reach ferromagnetic free layer 27, which is strong. A torque of 38 is applied to align the spins of the magnetic layer 1 27.
• the magnetization of the ferromagnetic free layer 27 is antiparallel to the ferromagnetic fixed layer 26. It becomes. As a result, the large number of spin electrons 37 do not reach the ferromagnetic free layer 27 as compared with the case without the Ru layer .28, and the magnetization can be reversed with a smaller current density.
• the spin injection device 16 of the present embodiment the spin of the spin polarization section 9 is fixed and the spin is injected, and the ferromagnetic free layer 27 and the non-magnetic layer 28, In the ferromagnetic fixed layer 29, the magnetization reversal of the ferromagnetic free layer 27 can be performed at a low current density.
• the magnetization reversal force of the ferromagnetic free layer 27 occurs, the magnetization becomes parallel or antiparallel to the magnetization of the ferromagnetic fixed layer 26, so that the antiferromagnetic layer 21 and the ferromagnetic fixed layer
• the layer structure including the injection junction 7 composed of the nonmagnetic metal layer 25 and the nonmagnetic metal layer 25 such as Cu and the ferromagnetic free layer 27 has a giant magnetoresistance effect similar to that of the CPP type giant magnetoresistance element. Occurs.
• the nonmagnetic layer 7 is an insulating layer 12 capable of tunnel junction
• the magnetization reversal of the ferromagnetic free layer 27 occurs, a tunnel junction between the antiferromagnetic layer 1 and the ferromagnetic fixed layer 26 is possible.
• the layer structure including the insulating layer 12 and the ferromagnetic layer 27 has a tunnel magnetoresistive effect as in the case of the CPP type tunnel magnetoresistive element.
• FIG. 8 is a schematic diagram of the spin injection magnetic device of the present invention.
• the spin injection magnetic device 30 has a ferromagnetic spin in which a Sy AF 3 serving as a free layer and a fixed layer 31 composed of a ferromagnetic layer 32 and an antiferromagnetic layer 34 are tunnel-juncted with an insulating layer 33.
• the tunnel junction (MTJ) element 36 includes a spin injection part 1 for reversing the magnetization of a free layer, which is a ferromagnetic layer.
• the spin injection section 1 is obtained by forming the injection junction into an insulating layer 12 capable of tunnel junction.
• the spin injection device 14 may have a two-layer structure including the ferromagnetic free layer 27 and the nonmagnetic layer 28 provided on the ferromagnetic free layer.
• SyAF 3 is provided on the ferromagnetic free layer 27, the nonmagnetic layer 28, and the nonmagnetic layer of the spin injection device 16 of the fourth embodiment shown in FIG. A configuration in which the magnetic layer 29 is replaced with a three-layer structure may be employed.
• the spin injection magnetic device of the present invention can be used for a super-gigabit large-capacity, high-speed nonvolatile memory.
• a free layer of SyAF is sandwiched or covered with an insulating film capable of tunnel junction, and coupled as a lead wire at a spin-injection portion corresponding to this SyAF to perform fine processing.
• the basic structure of the MRAM / spin transfer magnetic memory device can be obtained.
• the free layer is a two-layer structure composed of a ferromagnetic free layer 27 and a nonmagnetic layer 28 or a strong layer provided on the ferromagnetic free layer 27, the nonmagnetic layer 28, and the nonmagnetic layer, in addition to SyAF.
• a three-layer structure including the magnetic layer 29 can be used.
• FIG. 9 is a sectional view of a magnetic thin film that can be used in the present invention.
• a C 0 2 F e XCr to XA 1 thin film 43 is provided on a substrate 42 at room temperature. Where 0 ⁇ x ⁇ 1.
• the C 0 2 F e x C r,-XA 1 thin film 43 is ferromagnetic at room temperature, has an electrical resistivity of about 190 w ⁇ cm, and has a B 2 , A2 structure.
• the thickness of the C o 2 F e x CI -XA l thin film 4 3 on the substrate 4 2 may be one less than 1 nm.
• FIG. 10 is a sectional view of a modification of the magnetic thin film that can be used in the present invention.
• the magnetic thin film 45 used in the present invention is different from the structure of the magnetic thin film 41 in FIG. 9 in that the substrate 42 and the C 0 2 F Ex Cr A 1 (here, 0 ⁇ x ⁇ 1) thin film 43 are used. A buffer layer 44 is inserted between them. By inserting buffer layer 44, C o 2 F on substrate 4 2 ex C r, _x A l (here, 0 ⁇ x ⁇ l) The crystallinity of the thin film 43 can be further improved.
• the substrate 4 2 used in the magnetic thin film 4 1, 4 5, the thermal oxidation S i, multi crystal such as glass, MgO, can be formed using a single crystal such as A 12 ⁇ 3, GaAs.
• the buffer layer 44 Al, Cu, Cr, Fe, Nb, Ni, Ta, NiFe, or the like can be used. (Wherein, 0 ⁇ X ⁇ 1) the C o 2 F e x C r preparative x A 1 thickness of the thin film 4 3, 1 or more 1 nm; may be at or less. If this film thickness is less than 1 nm, it becomes substantially difficult to obtain any one of the L 2, B 2, and A 2 structures described later. The application as an injection device becomes difficult, which is not preferable.
• Figure 1 1 is, C 0 2 F e x C r used in the magnetic thin film, - x A 1 (wherein, 0 ⁇ X ⁇ 1) is a diagram schematically illustrating the structure of a.
• the structure shown in the figure is eight times (two times the lattice constant) that of a conventional unit cell of bcc (body-centered cubic lattice).
• the composition ratio of F e and C r is F e x C r, -x (where 0 ⁇ x ⁇ 1), and [AI is placed at position I, and Co is placed at positions III and IV.
• the structure of Co 2 F e x Cr -! ( Here, 0 ⁇ x ⁇ l) x A l film 4 3 are ferromagnetic at room temperature, and, without heating the substrate, B 2, A2 C o 2 F e x C r what Re or one structure of structure, -x a 1 film is obtained.
• the C o 2 F e x C r, -x A l thin film 4 3 (here, 0 ⁇ 1) having the above configuration has L 2,, B Any one of the 2, A2 structures is obtained.
• the B 2 structure of the Co 2 Fe x Crt-x Al (here, 0 ⁇ x ⁇ 1) thin film is a unique substance that has not been obtained conventionally.
• the B2 structure is similar to the L2, structure except that the L2, structure has a regular arrangement of Cr (F e) and A1 atoms, whereas the B2 structure is not. It is arranged in a rule.
• the A2 structure is a structure in which Co, Fe, Cr and A1 are irregularly substituted. These differences can be measured by X-ray diffraction. '
• the magnetic thin films 41 and 45 having the above configuration are half-metal, but qualitatively, a tunnel magnetoresistive element with a tunnel junction was fabricated and it exceeded 100%. If it shows such a very large TMR, it can be considered as half metal.
• Co 2 F e x C r! -X A 1 on one side of the insulating film (0 ⁇ x ⁇ 1) using the thin film 43 as a ferromagnetic layer, spin polarizability to the other ferromagnetic layer of the insulating film is 0.5
• a large TMR exceeding 100% was obtained.
• the reason why such a large TMR can be obtained is that the Co 2 Fe x Cr, -x Al (0 ⁇ x ⁇ l) thin film 43 has a large spin polarizability, L 2 1, B 2, a 2 or one of the structures of the structure is based on the discovery that obtained.
• the C 0 2 F e x C r I— x A 1 (0 ⁇ x ⁇ 1) thin film 43 is ferromagnetic with a thickness of 1 nm or more. Characteristics can be obtained. This is because the interface of the tunnel junction can be made clean and sharp without oxidizing the surface or increasing the surface roughness. Big TM It is presumed that R can be obtained.
• the magnetic thin films 41 and 45 can be used for the first and second magnetic layers of SyAF 3 used in the spin injection device of the present invention, or the ferromagnetic layer 9 of the spin injection part.
• the magnetic thin films 41 and 45 are composed of an antiferromagnetic layer 21 and a ferromagnetic pinned layer 26 used for the spin injection devices 14 and 16 of the present invention, a nonmagnetic metal layer 25 such as Cu, and a ferromagnetic free layer.
• CPP type giant magnetoresistive element structure with a layer structure consisting of 28, a layer consisting of an antiferromagnetic layer 21 and a ferromagnetic pinned layer 26, an insulating layer 12 capable of tunnel junction, and a ferromagnetic free layer 27 It can be used for a tunnel magnetoresistive effect element structure. Further, it can be used for the ferromagnetic layer of the MTJ element or the tunnel magnetoresistance effect element used in the spin injection magnetic device of the present invention.
• FIG. 12 is a diagram showing a cross section of a magnetoresistive element using a magnetic thin film according to the second embodiment of the present invention.
• FIG. 12 shows the case of a tunnel magnetoresistance effect element.
• the tunnel magneto-resistance effect element 50 for example, Co 2 F e x C r have x A l (0 ⁇ 1) thin film 4 3 is disposed on the substrate 4 2, a tunnel layer It has a structure in which an insulating layer 51, a ferromagnetic layer 52, and an antiferromagnetic layer 53 are sequentially stacked. '
• the antiferromagnetic layer 53 is used for a so-called spin-bubble structure in which the spin of the ferromagnetic layer 52 is fixed.
• C o 2 F e x C r ix A 1 (0 ⁇ x ⁇ 1) thin film 43 pretend more, referred to as the ferromagnetic layer 52 pinned layer.
• the ferromagnetic layer 52 may have either a single-layer structure or a multi-layer structure.
• the A 1 Ox is an oxide of A 1 2 ⁇ 3 and A 1 in the insulating layer 5 1, C oF e
• the ferromagnetic layer 54, N i F e or, the CoF e and N i F e A composite film or the like can be used, and IrMn or the like can be used for the antiferromagnetic layer 53. Further, it is preferable that a nonmagnetic electrode layer 54 serving as a protective film is further deposited on the antiferromagnetic layer 53 of the tunnel magnetoresistance effect element 50 of the present invention.
• FIG. 13 is a view showing a cross section of a modified example of the magnetoresistive element using the magnetic thin film according to the second embodiment of the present invention.
• Magnetoresistive element using the magnetic thin film of the present invention Tunnel magnetoresistance effect element 5 5 is a child, more buffers on the substrate 4 2 4 4 and C 0 2 F e x C n- X Al (0 ⁇ x ⁇ 1) thin film 4 3 is arranged, the tunnel layer It has a structure in which an insulating layer 51, a magnetic thin film 52, an antiferromagnetic layer 53, and a nonmagnetic electrode layer 54 as a protective film are sequentially laminated.
• FIG. 13 differs from the structure of FIG. 12 in that a buffer layer 44 is further provided in the structure of FIG. Other structures are the same as in FIG.
• FIG. 14 is a view showing a cross section of a modified example of the magnetoresistive element using the magnetic thin film according to the second embodiment of the present invention.
• Tunnel magnetoresistance effect element 6 0 is a magnetic resistance effect element using a magnetic thin film of the present invention, more buffers on the substrate 4 2 4 4 and o 2 F e x C r, - X Al (0 ⁇ x ⁇ 1) thin film 4 3 is disposed, the insulating layer 5 1 as a tunnel layer, and C o 2 F e x C r Bok x Al (0 ⁇ 1) thin film 5 6, the antiferromagnetic layer 3 And a non-magnetic electrode layer 5 serving as a protective film.
• FIG. 14 differs from the structure of FIG.
• the ferromagnetic layer 52 serving as the pinned layer in FIG. 13 is also a magnetic thin film of the present invention C 0 2 F e x C r A 1 (0 ⁇ x ⁇ l) This is the point that a thin film 56 was used.
• Other structures are the same as in FIG.
• the substrate 4 2 used for the tunneling magnetoresistive element 5 0, 5 5, 6 0, thermal oxidation S i polycrystalline, such as glass, Mg O, single crystal such as A l 2 ⁇ 3, GaAs It may be.
• a 1, Gu, Cr, Fe, Nb, i, Ta, NiFe, and the like can be used for the buffer layer 44.
• the C o 2 F e x C r , - x A 1 (0 ⁇ x ⁇ 1) thin film 4 3 film thickness may be at 1 ⁇ M or less than 1 nm.
• the tunnel magnetoresistive elements 50, 55, and 60 of the present invention having the above-described structure are formed by sputtering, vapor deposition, laser ablation, or the like. It can be manufactured using a normal thin film forming method such as a masking method or an MBE method, and a masking step for forming an electrode having a predetermined shape.
• tunnel magnetoresistive element 50 and 55 which are the magnetoresistive elements using the magnetic thin film of the present invention will be described.
• the magnetoresistive elements 50, 55 using the magnetic thin film of the present invention use two ferromagnetic layers 43, 52, one of which is close to the antiferromagnetic layer 53, and the adjacent ferromagnetic layer 52, Since the spin valve type is used to fix the spin of the layer, when an external magnetic field is applied, the other ferromagnetic layer is a free layer of Co 2 F e x C r, -x A 1 (0 ⁇ x ⁇ 1) Only the spin of the thin film 43 is reversed.
• the magnetization of the ferromagnetic layer 52 by the spin valve effect since spin is fixed in one direction by the exchange interaction with the antiferromagnetic layer 53, a free layer C o 2 F e x C r i- x A 1 (0 ⁇ x ⁇ 1) Spin parallel and anti-parallel of the thin film 43 can be easily obtained, and the ferromagnetic layer is C 0 2 F e x Cr ix A l (0 ⁇ 1) Since the thin film 43 has a high spin polarizability, the TMR of the tunnel magnetoresistive element of the present invention becomes very large.
• the tunnel magnetoresistive elements 50 and 55 of the present invention are suitable for magnetic devices such as MRAM which require magnetization reversal with low power.
• tunnel magnetoresistance effect element 60 which is a magnetoresistance effect element using the magnetic thin film of the present invention will be described.
• the tunnel magnetoresistance effect element 60 is the same as the ferromagnetic Co 2 F ⁇ ⁇ C r, -x A 1 (0 ⁇ x ⁇ l) thin film 43 in which the pinned ferromagnetic layer 56 is also a free layer. (0 2 F e x C r , - because of the use of x a 1 (0 ⁇ x ⁇ 1), the equation (1) denominator Ri decreases good, yet, a tunnel magnetoresistance effect element of the present invention As a result, the tunnel magnetoresistance effect element 60 of the present invention is suitable for a magnetic device such as an MRAM that requires magnetization reversal with low power.
• FIG. 15 shows the magnetoresistance effect using the magnetic thin film according to the third embodiment of the present invention.
• FIG. 3 is a view showing a cross section of the result element.
• the magnetoresistive element using the magnetic thin film of the present invention is a giant magnetoresistive element.
• the giant magnetoresistive element 70 has a buffer layer 44 and a Co 2 FG x Cr, -X A l (0 ⁇ x ⁇ l) W43 of the present invention, which becomes a ferromagnetic material, on a substrate 42.
• Nonmagnetic metal layer 61 a nonmagnetic metal layer 61, a ferromagnetic layer 62, and a nonmagnetic electrode layer 54 serving as a protective film are sequentially laminated.
• a voltage is applied between the buffer layer 44 of the giant magnetoresistive element and the electrode layer 5.
• An external magnetic field is applied in parallel within the film plane.
• the current from the fur layer 44 to the electrode layer 54 can be caused to flow by a CPP structure which is a type in which a current flows in a direction perpendicular to the film surface.
• FIG. 16 is a view showing a cross section of a modified example of the magnetoresistive element using the magnetic thin film according to the third embodiment of the present invention.
• the giant magnetoresistive element 75 of the present invention is different from the giant magnetoresistive element 70 of FIG. 15 in that an antiferromagnetic layer 53 is provided between the ferromagnetic layer 62 and the electrode layer 54 to provide a spin valve type giant magnetoresistive element. This is a magnetoresistive effect element.
• Other structures are the same as those in FIG.
• the antiferromagnetic layer 53 functions to fix the spin of the ferromagnetic layer 62 that is to be the adjacent pin layer.
• a voltage is applied between the buffer layer 44 of the giant magnetoresistive elements 70 and 75 and the electrode layer 54.
• the external magnetic field is applied in parallel in the film plane.
• the current from the fur layer 44 to the electrode layer 54 can be caused to flow by a CPP structure which is a type in which a current flows in a direction perpendicular to the film surface.
• the giant magnetoresistive effect element 70, 75 of the substrate 42 is thermally oxidized S i, polycrystalline, such as glass, further, it is possible to use Mg_ ⁇ , a single crystal such as A 12 0 3, GaAs.
• Mg_ ⁇ a single crystal such as A 12 0 3, GaAs.
• Al, Cu, Cr, Fe, Nb, Ni, Ta, NiFe, or the like can be used as the buffer layer 44.
• As the nonmagnetic metal layer 61, Cu, A1, or the like can be used.
• CoF e as ferromagnetic layers 6 2, N i F e, C o 2 F e x Cr i - from x A l (0 ⁇ x ⁇ 1) any one or, or these materials, such as a thin film Composite membrane can be used.
• the C o 2 F e x C r , - thickness of x A 1 (0 ⁇ x ⁇ 1) thin film 43 may be any ⁇ 1 m or more 1 nm. When this film thickness is less than 1 nm, it is virtually impossible to obtain any one of the L 2 i, B 2, and A 2 structures. If the film thickness exceeds 1, application to a giant magnetoresistance effect element becomes difficult, which is not preferable.
• the giant magnetoresistive element 70, 75 of the present invention having the above-described structure can be formed by a conventional thin film forming method such as a snutter method, a vapor deposition method, a laser ablation method, an MBE method, and a predetermined shaped electrode. It can be manufactured by using a mask process for forming a mask.
• the giant magnetoresistive element 70 which is a magnetoresistive element using the magnetic thin film of the present invention, has a ferromagnetic layer of Co 2 F e x Cr to x A l (0 ⁇ x ⁇ 0.6) thin film 43. Since the spin polarizability is large, spin-dependent scattering is large and a large magnetoresistance, that is, GMR is obtained.
• the spin of the ferromagnetic layer 62 which is a pin layer, is fixed by the antiferromagnetic layer 53. cage, by applying an external magnetic field, a free layer Co 2 F e x C r, - becomes x a l (0 ⁇ x ⁇ l) state parallel to the antiparallel spin thin film 43 by an external magnetic field .
• the C 0 2 F e x Cr A 1 (0 ⁇ x ⁇ 1) thin film 43 has a large spin polarizability and therefore a large spin-dependent scattering, and also has a large resistance, so that the reduction of GMR due to the antiferromagnetic layer 53 is suppressed. it can.
• FIG. 17 is a diagram schematically illustrating resistance when an external magnetic field is applied to a tunnel magnetoresistive element or a giant magnetoresistive element which is a magnetoresistive element using the magnetic thin film of the present invention.
• the horizontal axis in the figure is the external magnetic field applied to the magnetoresistive element using the magnetic thin film of the present invention, and the vertical axis is the resistance.
• the magnetoresistance effect element using the magnetic thin film of the present invention is sufficiently applied with a voltage necessary for obtaining a giant magnetoresistance effect and a tunnel magnetoresistance effect.
• the resistance of the magnetoresistive element using the magnetic thin film of the present invention shows a large change due to an external magnetic field.
• an external magnetic field is applied from the area (I)
• the external magnetic field is reduced and set to zero, and the external magnetic field is reversed and increased, the area is changed from the area (II).
• region (III) the resistance changes from the minimum resistance to the maximum resistance.
• the external magnetic field in the region ( ⁇ ) be.
• a resistance change from the region (III) to the region (V) via the region (IV) can be obtained.
• a magnetoresistive effect element using a magnetic thin film of the present invention a region (I), in an external magnetic field in the region (V), a ferromagnetic layer 6 2 and the free layer Co 2 F e x C r, -x A 1 (0 ⁇ x ⁇ 1)
• the spins of the thin film 43 are parallel, and in the region ( ⁇ ), they are antiparallel.
• the magnetoresistance change rate is expressed by the following equation (4) when an external magnetic field is applied. The larger this value is, the more desirable the magnetoresistance change rate is.
• the magnetoresistive element using the magnetic thin film of the present invention has a magnetic field as shown in FIG.
• a magnetic field that is slightly larger than zero to ⁇ ⁇ that is, a low magnetic field
• a large magnetoresistance change rate can be obtained.
• the magnetoresistive element using the magnetic thin film of the present invention exhibits a large TMR or GMR in a low magnetic field at room temperature.
• a magnetic element can be obtained.
• the magnetoresistive effect element using the magnetic thin film of the present invention exhibits a large TMR or GMR at room temperature in a low magnetic field, and thus has a high sensitivity readout magnetic head and various magnetic heads using these magnetic heads.
• a magnetoresistive element using the magnetic thin film of the present invention for example, MTJ elements are arranged in a matrix, and a current is applied to a separately provided wiring to apply an external magnetic field.
• a magnetic device such as an MRAM can be configured by performing reading using the TMR effect or the like.
• the GMR element having a CPP structure which is the magnetoresistive element of the present invention
• the capacity of magnetic devices such as a hard disk drive (HDD) and MRAM can be increased.
• Example 1 corresponds to the structure of the spin injection device 14 shown in FIG.
• the layer made of Ta and Cu on the thermally oxidized Si substrate and the uppermost layer is a layer to be an electrode.
• C u is injected joint 7 there.
• F e,. and R u are ferromagnetic pretending one which is arranged on the C u layer 2 7 and the non-magnetic layer 2 8 nonmagnetic layer 7.
• this film was finely processed by electron beam lithography and Ar ion milling to produce a spin injection device 14 as shown in FIG.
• the element size is 300 ⁇ 100 nm 2 .
• FIG. 18 is a diagram showing the spin injection magnetization reversal of the spin injection device 14 of Example 1 at room temperature.
• the horizontal axis indicates the spin injection device current (mA) when the current from the ferromagnetic free layer 27 to the ferromagnetic fixed layer 26 is in the positive direction
• the vertical axis indicates the resistance ( ⁇ ) at that time.
• an external magnetic field H was applied to the spin injection device 14 to bring it into an antiparallel state, that is, an initial state with high resistance.
• the external magnetic field H at this time is 5 O Oe (oersted) (see A in FIG. 18).
• the resistance can be changed by changing the direction of the current flowing through the spin injection device 14 to cause the magnetization reversal of the ferromagnetic free layer 27.
• Example 2 corresponds to the structure of the spin injection device 16 shown in FIG.
• the layer composed of Ta and Cu on the thermally oxidized Si substrate and the uppermost layer is a layer to be an electrode.
• Cu is injected joints 7.
• C 0 alloy Co 9 .F e,., Ru, Co 9 .F e !. are the ferromagnetic free layer 27, non-magnetic layer 28, ferromagnetic layer disposed on Cu of the non-magnetic layer 7, respectively.
• the spin injection device 16 of the second embodiment differs from the spin injection device 14 of the first embodiment in that Co 9 is used .
• a spin injection device 16 having an element size of 100 ⁇ 10 O.nm 2 was produced in the same manner as in Example 1.
• FIG. 19 is a diagram showing the spin injection magnetization reversal of the spin injection device 16 of Example 2 at room temperature.
• the horizontal axis shows the spin injection device current (mA) when the current from the ferromagnetic free layer 27 to the ferromagnetic fixed layer 26 is in the positive direction
• the vertical axis shows the resistance ( ⁇ ) at that time.
• the external magnetic field H applied to make the initial state of high resistance is 150 ⁇ e.
• the spin injection device 16 of the second embodiment has a current of about 0.2 mA and a resistance change, and the magnetization reversal occurs, similarly to the spin injection device 14 of the first embodiment. You can see that.
• This magnetization reversal The required current density was 1 ⁇ 10 6 AZcm 2 . This value is about 1/24 of Example 1 and about 1/200 of that of Comparative Example described later. The magnetoresistance was about 1%, which was the same value as the magnetoresistance (MR) of the comparative example described later. As described above, the current density required for magnetization reversal could be reduced by setting the thickness of the nonmagnetic layer 28 to 6 nm.
• Example 3 relates to a structure corresponding to FIG.
• CogoF e .o (1 nm) / Ru (0. 45 nm) / C o 90 F e 10 (1. 5 nm) is S i 0 2 It was found to be in the form of particles having only one layer dispersed therein, and to have a double tunnel structure with SiO 2 as an insulating matrix. For this structure, a voltage was applied between the upper and lower Cu and Ta films to flow a current, and the resistance at that time was measured at room temperature while changing the current.As a result, a jump in resistance was observed at about 0.1 mA. did.
• the comparative example has a structure in which an antiferromagnetic layer is further provided on the first ferromagnetic layer 101 having a three-layer structure used in the conventional spin inversion method shown in FIG. That is, as a structure without a Ru layer in the spin injection device 14 of Example 1, Ta (2 nm) / Cu (20 nm) / IrMn (10 nm) / Coi) was formed on a thermally oxidized Si substrate. . F ei. (bnm) / Cu (6nm) / Co9. F e io (2.5 n m) / Cu (5 nm) / Ta (2 nm) were sequentially sputtered. Next, the element size was set to 300 ⁇ 100 nm 2 in the same manner as in Example 1.
• FIG. 20 is a diagram showing (a) a magnetoresistance curve and (b) a spin transfer magnetization reversal of the comparative example at room temperature.
• the horizontal axis is the applied magnetic field (Oe)
• the vertical axis is the resistance ( ⁇ ).
• the device current is 1mA.
• the reluctance was measured by sweeping the external magnetic field from zero (see G in Fig. 20 (a)).
• the magnetoresistance (MR) of the comparative example is 1.1%, which is the same as the value previously reported.
• the horizontal axis represents the current (mA) when the current flows from the second ferromagnetic layer 103 to the first ferromagnetic layer 101 in the positive direction.
• the vertical axis shows the resistance ( ⁇ ) at that time.
• the current density required for the magnetization reversal was lower than that in the comparative example.
• the current density required for the magnetization reversal is 1 ⁇ 10 6 A / cm 2 , It was found that the value could be reduced to a value of / 10.
• FIG. 21 is a diagram showing the result of measuring the X-ray diffraction of the C 0 2 Fe 0.5 Cro. 5 A 1 thin film 43.
• the horizontal axis of the figure is the diffraction angle 2 ⁇ (degrees), and the vertical axis is the intensity of the diffracted X-rays on a L 0 g (logarithmic) scale.
• downward arrows shown in FIG. (I) represents the diffraction intensity from each side of the Co 2 F ⁇ ⁇ . 5 C r 0. Of 5 A 1 film 43 crystals.
• a Co 2 F e x C r ix A 1 (here, 0 ⁇ 1) thin film 43 is formed using an appropriate buffer layer 4 such as Cr or Fe. Or Co 2 F e x Cr, -x A l (where 0 ⁇ x ⁇ l) If the amount of F e substitution with respect to C r of the thin film 43 is reduced, (1 1 1) A diffraction X-ray peak on the surface was confirmed. This is C 0 2 F e x C r! One x A 1 (where 0 ⁇ 1) indicates that the thin film 43 has an L 2 i structure.
• FIG. 5 is a diagram showing the magnetization characteristics of a 0.5 Cr 0.5 A 1 thin film 43 at room temperature.
• the horizontal axis of the figure is the magnetic field H (0 e), and the vertical axis is the magnetization (emu / cm 3 ).
• C o 2 F e 0. 5 C r o. 5 A l film 4 3 is a ferromagnetic indicates hysteresis. From the figure, it was found that the saturation magnetization was about 300 emu / cm 3 and the coercive force was 5 Oe ( ⁇ e).
• the magnetic thin films 41 and 45 using the same Co 2 Fe 0.5 Cr O. 5 A 1 thin film 43 were prepared by changing the temperature of the substrate 42, but up to 400 ° C. Saturation magnetization and coercivity hardly changed. Therefore, it is suggesting that the room temperature C 02 already good crystallinity B 2 structure F e 0. 5 C r 0. 5 A l thin film 4 3 is obtained. In addition, at room temperature, Co 2 Fec. 5 Cr. As a result of measuring the electric resistivity of the .5 A1 thin film 43, the electric resistivity was about 190 ⁇ ⁇ cm. This value is equivalent to 200 ⁇ ⁇ cm of the antiferromagnet InMn.
• a spin-valve tunneling magnetoresistive element 55 shown in Fig. 13 was fabricated at room temperature.
• a high frequency sputtering device and a metal mask Cr is used as a buffer layer 44 on a thermally oxidized Si substrate 42, and Cr (5 nm) / Co 2 Fe 0.4 Cr. . 6
• the numbers in parentheses are the respective film thicknesses.
• a 1 thin film 43 is a ferromagnetic free layer
• a 1 ⁇ x is a tunnel insulating layer 51
• C 0 Fe and N i Fe are pinned layers of a ferromagnetic layer 52
• IrMn is an antiferromagnetic layer 53, which has a role of fixing the spin of the ferromagnetic layer 52 of CoFe / NiFe.
• the Cr on the antiferromagnetic layer 53, I r Mn, is the protective film 5.
• a uniaxial anisotropy was introduced into the film surface by applying a magnetic field of 1000 e during film formation.
• FIG. 23 is a diagram showing the magnetic field dependence of the resistance of tunneling magneto-resistance effect element 55.
• the horizontal axis in the figure is the external magnetic field H (0 e), and the vertical axis is the resistance ( ⁇ ). From this, the TMR was determined to be 107%.
• the TMR obtained by the tunneling magneto-resistance effect element 55 of the present invention is very large considering that the TMR of the conventional tunneling magneto-resistance effect element is about 50% at the maximum, and Co 2 Fe 0.4 Cro. It was found that the spin polarizability of the 6 A 1 thin film was as high as about 0.7.
• Example 7 Using 20 nm of F e as a buffer even 44, and C o 2 F e 0. 6 C r 0 .4 except for using the A 1 thin film 3, the same spin-valve tunnel magnetoresistive Example 5 Element 55 was produced. An external magnetic field was applied to the tunnel magnetoresistive element 55, and the magnetoresistance was measured at room temperature. The result was a 92% TMR. This indicates that the spin polarizability of the Co 2 Feo.6Cr.4A1 thin film is high.
• Example 7 Example 7
• FIG. 24 is a diagram showing the magnetic field dependence of the magnetoresistance of the tunnel magnetoresistance effect element 50.
• the horizontal axis in the figure is the external magnetic field H (Oe)
• the left vertical axis is the resistance ( ⁇ )
• the right vertical axis is the TMR (%) calculated from the measured resistance.
• the solid and dotted lines in the figure show the resistance when the external magnetic field is swept.
• a spin-valve tunneling magneto-resistance effect element 50 using the Co 2 FeAl magnetic thin film 43 was produced in the same manner as in Example 6 without using the buffer layer 44.
• the C 0 2 FeAl magnetic thin film 43 had an A 2 structure.
• An external magnetic field was applied to the tunnel magnetoresistance effect element 50, and the magnetoresistance was measured at room temperature and a low temperature of 5K.
• the result was a large TMR of 8% at room temperature and 42% at low temperatures. This suggests that the Co 2 FeAl magnetic thin film having the A2 structure also has a large spin polarizability.
• Co 2 FeAl (10 nm) / A 1 O x (1.4 nm) / CoFe (3 nm), which is a tunneling magnetoresistance ) / Ta (10 nm) was fabricated at room temperature.
• the numbers in parentheses are the respective film thicknesses.
• the above-described coercive force difference type tunnel magnetoresistive effect element is a tunnel magnetoresistive effect element utilizing a difference in coercive force between ferromagnetic materials C02FeAl and CoFe.
• the TMR of this coercive force difference type tunneling magneto-resistance effect element shows a difference in magnetoresistance depending on whether the magnetization is parallel or anti-parallel to each other, similarly to the spin valve type tunneling magneto-resistance effect element.
• the TMR values obtained by the fabricated coercive force tunneling magnetoresistive element were 8% at room temperature and 42% at a low temperature of 5K.
• this tunnel magnetoresistance effect element was heat-treated at various temperatures in a vacuum, and the TMR characteristics of each element were measured.
• the TMR when heat-treated at 300 ° C for 1 hour was 28% at room temperature and 55% at a low temperature of 5 K, which was much higher than the TMR when manufactured at room temperature.
• the crystal structure of the Co 2 FeAl thin film at this time was measured by X-ray diffraction, the crystal structure was an L 2 structure.
• the improvement in TMR by the above heat treatment is due to the change in the crystal structure of the Co 2 FeAl thin film from the A2 structure to the structure, which suggests that the spin polarizability of the structure is larger than that of the A2 structure.
• a spin-valve tunneling magneto-resistance effect element 50 was produced in the same manner as in Example 5, except that GaAs was used as the substrate 44. In this case, C 0 2 Fe 0. 4 Cr 0.6 A 1
• the magnetic thin film 43 is L 2! It was a structure. An external magnetic field was applied to the tunnel magnetoresistance effect element 50, and the magnetoresistance was measured at room temperature. As a result, a large TMR of 115% was obtained at room temperature, and the structure Co 2 Fe 4. It was suggested that the spin polarizability of the 6 A 1 magnetic thin film was very large.
• a giant magnetoresistive element 75 of spin valve type shown in FIG. 16 was fabricated at room temperature. Using a high frequency sputtering apparatus and the metal mask, on the thermal oxide S i substrate 42, A1 (100 nm) / C 0 2 F e 0. 5 C r 0. 5 A 1 (5 nm) / Cu (6 nm) 5Cro.5A1 (5nm) / NiFe (5nm) / IrMn (10nm) / Al (10Onm) A multilayered structure of a valve-type giant magnetoresistive element was fabricated. The numbers in parentheses are the respective film thicknesses.
• a 1 is a buffer layer 44, C 0 2 Fe 0.5 Cr 0 .s
• a 1 is a thin film 43 serving as a free layer
• Cu is a nonmagnetic metal layer 61 for exhibiting a giant magnetoresistance effect. is there.
• the two-layer structure of 5 A 1 (5 nm) and N i Fe (5 nm) is a ferromagnetic layer 62 serving as a pinned layer.
• IrMn is the antiferromagnetic layer 53, which has a role of fixing the spin of the ferromagnetic layer 62 serving as the pin layer.
• the uppermost layer A1 is the electrode 54.
• a magnetic field of 100 ⁇ e is applied to create uniaxial anisotropy in the film plane. Introduced.
• the deposited multilayer film was finely processed using electron beam lithography and an Ar ion milling device to produce a giant magnetoresistive element 75 of 0.5 ⁇ mx 1.
• a voltage was applied between the upper and lower electrodes 44 and 54 of the device, a current was passed in the direction perpendicular to the film surface, and an external magnetic field was applied to measure the magnetoresistance at room temperature. As a result, a magnetic resistance of about 8% was obtained.
• This value is eight times as large as that of the conventional giant magnetoresistive element with a spin / rev CPP structure of less than 1%. Accordingly, the Co 2 Fe that makes the GMR of the giant magnetoresistive element having the CPP structure of the present invention much larger than the GMR of the giant magnetoresistive effect element having the conventional spin-valve CPP structure is very large. 0 .5 C r o. 5 a 1 spin polarization of the thin film 43 is divide to be due high particular.
• the spin injection device of the present invention magnetization reversal can be caused with a small current density. Further, the spin injection magnetic device of the present invention can cause the magnetization reversal of the MTJ free layer by spin injection at a smaller current density. Therefore, it can be used for various magnetic devices and magnetic memory devices, such as ultra-gigabit large capacity, high speed, nonvolatile MRAM.
• L 2!, B 2, Co 2 having any one of structures A 2 structure F e x Cr A1 (wherein, 0 ⁇ Kai ⁇ 1) magnetic thin film with the It can be manufactured at room temperature without heating. Furthermore, it shows ferromagnetic properties and has a large spin polarizability.
• L2 of the present invention B 2, A C 0 2 F having 2 or one of the structures of the structure (wherein, 0 ⁇ x ⁇ l) e x Cr ix Al according to the giant magnetoresistance effect element using a magnetic thin film, at room temperature, it is possible to obtain a very large GMR in low external magnetic field. Similarly, a very large TMR can be obtained with a tunnel magnetoresistive element.
• a new magnetic device can be realized by applying the magnetoresistive effect element to various magnetic devices such as an ultra-gigabit large-capacity, high-speed magnetic head and non-volatile, high-speed MRAM.
• various magnetic devices such as an ultra-gigabit large-capacity, high-speed magnetic head and non-volatile, high-speed MRAM.
• the saturation magnetization is small, the magnetic switching field due to spin injection is small, so that magnetization reversal can be realized with low power consumption, and efficient spin injection into semiconductors is possible, and a spin FET is developed. Because of its potential, it can be widely used as a key material for pioneering the field of spin electronics.

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